After graduating from department of physics of Tsinghua University, Peng continued to pursue his postgraduate degree.
[3] Recommended by Born, Peng worked at Dublin Institute for Advanced Studies in Ireland as a postdoctoral scholar from 1941 to 1943 and later as an assistant professor from 1945 to 1947.
[4][5] From August 1941 to July 1943, Peng collaborated with Walter Heitler and James Hamilton to study cosmic ray, and developed HHP theory.
[6][7][8] Together with Born, Peng was awarded the Makdougall Brisbane Prize by the Royal Society of Edinburgh in 1945.
In the same year he received a personal invitation from Ireland's Taoiseach, Éamon de Valera.